Telephone-exchange system



\ W. G. BLAUVELT TELEPHONE EXCHANGE SYSTEM Feb. 23 1926.

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f w; G. BLAUVELT TELEPHONE EXCHANGE SYSTEM Filed May 2o, 1925 15snee'tS-shet 1s 'unnnnnun Sra/m n KNQQMQ Patented *y i u ann 'ramenantooMPANY',aQ

d-ToraZZ whom t may fconcewty g f ,y vle it known vthat, 1, .WILLIAMGrnBInm-v j VELT, a'citizen of the" United l States, 'residir-V1` y ingat New York,` in the county of New York and State of New York,have`invente/elfcerfA Tt-ain Improvements in Telephone-Exchange Systems,of which the fol-lowing' isla specl icationif: j f l 'The presentfinventionrelates to telephone exchange systems and particularly tosuch.;r 'Y #systems wherein connections are established A by means ofautomatic switches. 4 In the case` of power driven automatic-japparatus, adaptable for ri'ifiulti-oftice (areasp it is customary tomake selections `under the'. "fcontrol of a yregistersender whichy lisset'byfL tlie dialA interruptions"from fa subscribers 1j station :or byapparatus in? a `distant,jofiicejv sender. e Inxthis Y arrangenient V ofIselecting apparatus translators ,are providedA ortr-'ans-4 y latingtherecordolithe office'y code 11n' the sender into registrations such asmay be used- 'or selectingthe proper oilice. This ytrans-i lationoccupies only a small portion /oI- Jfjthe-v time interval.duringrwhichthev senderjis -employed and' since each translator fis made Y up .ofconsiderable apparatusLit is` desirable for economie reasons' toseparate the Ttrans- Y lz-.tor from the sender' in order that the numberof translators may be Vmaterially reduced. Hereto'fore suchtranslatorshave' been permanently associated Withregister senders. f, f Y It is anobject of the V)resentinvention to provide. common translatorsfwhichilnay bel.-

' selected for ,y use by any registersenders.4 u e theY'inver-itienfli'es ,in means Y A :feat-ure or fori positromnaffsel'ected 'translator uncle 40 the Control of AcountingY relays. fl@','shfoiifs'ifanothei set o reibist s fo f; 90 17,.: Y i I A v .p at

Another feature oi' the invention lies '-1 receivingrthe record astranslated.; 'Y

they provision "of a plurality'lof; .groups 'off translators `with meansfor discriminating"-r lbetween .groups ofv translators ,in accordance awith the code which they Vare adaptedto 'i translate. l. Y 'f i Theabove described invention hasA beenVr setter-th in connection With/atandem sender,that"is, a sendenwhicli is employed inv lagtarndernofiicefor receiving .desgna-- l tions frein originating ofticesand fo'transfer relay'sf'foir or registering the relay oneo'tga number y conHausa SYSTEM. f f 'l senderA of .thisl type States fpatentto, A issuedJuly'V 115, L1924..

Referring-'now tothe .dratviilgs?,y Figure 1` ,l u .v shWsindiagrammatic ,form afsubscrib'e s."l lin ;,ithl seleciOlTSffofiteizdingl'said vi111 `i @11d-.a sender lfr:.'.ClitrOll-ng'Suchjseltdrs, 1

,.-fligl Q -shows.a district selectorat'fa t'andenf'lO oliice. 'Y j 3shows anl outgoinglselector atth'e tandem office, the .incoming andrfinal selector), ata third oiiice and call indicator."apparatus'vvatfsti'll :another office. l

Y. .wwsal'nk circuiti@associating? meende lig2;

lotteeswth 'for alle 'j ,and @district y' selector -o 'e 6u f Eig, 7Lshows 'thelheans Or regering'.- impulsesl ronrV theA distaiit` office;z,and

irectin'glthe registratl ofsaidimpulses.` A' *l I Fig. 8 k'shows 'aregis call finfflicatorl fini pulses received y l 'Fig.: 9k showsthe'counting relays andfse- 80 quenee sWijteh'for controll'ingselections.i4 i.

, Fig. 10 shoWsa-sequence'switch and appa-[ ratusfo'f controlling'jthefselection and' seit-"5T` tingfoi the translater;Y

.1Fiig;flll"show`s. one of* a'y pluralityk Y.o v com. necting A switchesby. 'meansfj of whfieh thev translator is connected Witlrtlie senderflf'5* 15 shows; a translator'Av and 4 machine. Y A Fig. 16 shows themannerV of arranging Figs.` 1 to 15 to makeup the disclosure of thepresent invention;

K. Before proceeding i argine @de scription of the operation a briefsummary of the operation may be desirable.

When the subscriber at substation 100 in olice X removes his receiverfrom the hook, the line switch 101 functions to connect the line with anidle district selector such as the district selector 200 and also tohunt for an idle sender.

When the sender has been found, the district selector 200 causes thesender 104 to transmit code impulses corresponding to the completedesignation as registered on that sender, which impulses are recorded onthe registers ot'F ig. 8. As soon as the code registers of F ig. 8 havebeen set, the registration is transferred to the registers ot Fig. 11.According to the setting ot these registersone ot the relays 1007, 1011,1012 and 1013 are operated to start a finder switch, such as shown inFig. 14, hunting tor an idle translator in the group corresponding tothe relay operated. Each group of translators serves vto translate aparticular class of office codes. Four groups are provided in thepresent disclosure, two for codes dialed by subscribers directly and twofor those dialed by operators. The codes used by each class ot dialerare subdivided tor.

the purpose of rendering the maximum number of codes available. Thetranslator such as 1500 is then positioned under the control of theregisters of Fig. 11, the counting relays ot Fig. 9 and sequence switch1010 to select the terminals corresponding to the particular otlice codedialed. As soon as .translator1500 is positioned, circuits areestablished between the pulse machine 1550 and the register relays ofFig. 13 to set up thereon the designations necessary to Select the'desired oiice.

When the registeryrelays of Fig. 13 have been set, the translator isreleased, the class switch 1200 is positioned and selections arecompleted in the usual. manner. 1f the distant otlice is a manualotlice, code relay call indicator pulses are transmitted to indicate tothe operator at station Z the number ot the wanted subscriber.

Detailed description.

Assume that the subscriber at substation 100I located at olice X desiresto talk to a subscriber at substation 380 located at ottice Z which maybe reached only through the tandem oliice Y. The subscriber dials thenumber ot the wanted line. The line 100 will be extended, as briefly set:torth above, to office Y. For a description of the registration of thewanted number on the sender and the action ot said sender in controllingthe extension to the wanted line, reference tandem office, which it isassumed is district selector 200, a relay (not shown) at sender 104 willbe bridged across trunk conductors 249 and 250 completing a circuit forrelay 201 which may be traced trom battery at the outer lett backcontact of relay 234, lett winding ot relay 201, lower lett contact of lcam 203, upper back Contact ot relay 202,

over trunk conductor 249, through oirlceselector 103, and districtselector 102, through the above mentioned relay in the sender 104, backthrough district selector 102 and otlice selector 103, trunlr conductor250, inner lower back contact of relay 202, lower right contact ot cam204, right winding of relay 201, inner right back contact o1 relay 234to ground. The operation otl relay 201 closes a circuit from batterythrough the winding ot relay 205, lower right Contact of cam 206, outerlett back contact of relay 207, lower contacts of cam 208, front contactof relay 201 to ground.

Allotter switches 410 and 450 are so arranged that when one stands in aposition trom 1 to 10, the other stands in position 17. Let it beassumed tor this description that allotter 410 is in position 1.Therefore, when relay 205 operates it closes a circuit from ground atAits inner lett front contact, over the upper right and lower lettcontacts of cam 209, conductor 405, contact of key 404, lett backcontact of relay 403, lett back contact of relay 401, right contact ofcam 406, winding of relay 400 to battery. Relay 400 closes a circuitfrom battery through noneinductive resistance 407, winding of relay 408,outer contact ot relay 400 to ground. Relay 408 operates and closes acircuit trom battery through the winding of relay 503. lett back contactof relay 502, contact of jack 501, conductor 411, lett con-tact of cam409, cont-act of relay 403 to ground. Relay 503 in operating locks overits Vinner right Contact, right back contact ot relay/1 502, conductor504 to ground at the inner contact. ot relay 400.

Relay 503 in operating also closes a circuit from battery, through thewinding of relay 505, inner lett contact of relay 503 wreken? ationofrelay 05 will be discussedflater.l Relay 503 closes acircuitfextendingfrom battery through the.noneinductiveresistanoe-; 407,1niddleconta-ctof relay400, conductorA 506, lIniddle right contact Vof relay :503,conductor 507, left back'contact ofrelay 412y tofgroun'djl ThisycircuitY shunts the wind'-y i ingof relay 408 .andpermits-'thatrelay"toV release, thusuopening the energizing cir! cuit ofrelay y503. Avcircuit .is also? closed troni battery 'through the,windingfoi- "star-t magnet 510, back Contact of magnet 511,

Youter leftvcontact otrelay 503 to ground? The power driven `switch* 500.is rotated unk der the control .of magnet; 510 until brush j503 toground;

' 512 engages the terminal connected to the district selector -200 whichlterniinalfyis connected with'V ground, thuslclosing j a circuit `frombattery, through the winding or relay 508, andl from' battery throughthewinding of stop.. magnet l511 and backconta'ctof-revlay 518, inparallel, over ytheouter right contact-of relayer503, brush 512,;andtheterrn'il 25- nal corresponding to selector l200, rconductor 509,lower contactsvpof 'cani 212,1 outer left front- Contact of, relayl 205,right Contact j Y of cain 213 to ground.:

It will be noted hatpinthe case ofvia district selector vwhich'hasfnot'vbeen 'selected- 'lor use relay-205 will not b'fe'gcperatedvan'd thepathy from fgroundpwillnotv be extended f to a terminal associatedWithfbrush512g Ref,

lay 508 and magnet 511foperateeinthe above traced fc'ircuit, lmagnetl511 -seryinggtoi open thek circuit oir magnet 510,"bri`ng1ng\the switch500 toirestjon ltlieterlnina'ls leading toselec'tor 200;; ARelay 508closes afclrcuit fro-inlbatteiiy .through the winding-fof relay i518,outer"`riglit. front contact'o A relay 508 to groundnRelay 518s-operatesand closes, a locking clrcuit orjitselfover its inner,- right Vcontact,leiftfwinding-otrelay'519, brush513 v 505 Vvas previously described[closes a ',circuitY froin battery lthroiugh the. winding lof relay.530, right baci; contactotrelay*531, outer to fconductor? 528V fromwhence the circuit Vis extended to ground as iwilllbe subsequently Ydescribed..k Relay-518 also closesoanio-byious circuit for relay V:502,closes alylr'oldin circuit Y Relay 530k operates and locks over nits,Vright' for magnet 511Y at its vinner `left a ternate ',contact, andcloses ya new*holding circuit for relay 503 which extendsouertheinnerright .contact of relay T503, inner yrightv front' contactof relay-508,louterleft front contact of relayv 518, outer leftfrontcontact ofrelay v Theoperation@vv n tracedI locking. ci-rcuit for'.re'lay :503,: closes a holding cironitvfor relay 150,5zat its Vini'ddleif *Fright contact',.:an :l closes a circuit `from 'bate vtery throughthe left Swinding ,oflrela'y 20T,

Vupper left'and lower 'right contacts v of cani 2214, vconductor 529,-vbrush 51d. 'and ,its corlef Y spondingV terininallei`t iront-contactof'relay 502',`ler"t contactf-oflrelay508,1to ground. Y Relay' 207Yoperates' and loolrs .;QYer:-its outer Vleft front contact, lowerlcontacts of ca1n208,

the circuitfor relay508ff` 4relayf5tl2, opens theV to ground t frontcontact j of relay, j201i The popeijationzof relay -207 openstliefcireriitV`r of, relay l205 whichrelay releasesopening-- Y,

the oiroutof relay 4:00. Relay2071also'gconfv f f g i nectsr ground fromthe front' `contact' of re lay 20l-,. lowe r,` contacts of, canal 208,right front contact .otrelay 207, lower contacts of Y cam 215,non-induetive resistancel216, con-f ductor 528, coinpletingthe lockingcircuit Y 1 Relayfl207 Y also, closesraf circuit from baclrcontactof'relay .205, rgllt'contact or' switchi2101to positionlockingcircuit-ofv relay 5'18 isjext'e'nded over Y tlfieaipperriglitcontact of cani219 toground',

lwhere it is maintained until seduenceswitch .210,leayespositijon 13,The releasefof relay 205 as V previously described also reinoyes VaroundfromVv conductor 3509, thus opening Vi-jfllie release ofrelay508opensthelocking circuit-of relay 503 andthat relay also jre- `leases. Whensequence switch 210 reaches l positiong3, th'exfcirc-uitfof relay 2 01is ex# tended frenigbattery,xouter letbaclr conl ktact of relay 234,'fleftwinding. of 'relay 201,- "right Y contacts 4of earn 218,le-tt'vback-contact offrelay-205, lei't contacts oic carnl` 203,rc`on=ductor124l9and thence as previously traced Y to yconductorf*250,leftcontacts` of.;Ycanr-2 ()t,VA I Y v right b'a'clry contact rvof relayA205", right windf ing eig-relay l201, right contact of relay23'4e 'toground, so that'relayl201isniaintained' energizedf I 'f In the Ameantimeoiperatioii'of i right rontxcontactof relay ..505to' ground.`

front contact, Vback.contactV of :magnet Y'521, outer right contaotofYrelay 50,5 to ground,

V the winding of allotter' niagnet 410,1leitt lc011- all '.f tact ofca`1n1113, :conductor 532'," Contact of Y Ajack1501,' leftxfrontcontactof relay, 1505v to ground, advancing allotter "10 AIto 1 'p'o'sitiong2 Yin" whiclrposition it is read-y' tolallotl Vther link circuit for .use,in connection r i withafsubsequent call. l

flfhe operationof relay 530 closes .acircuit Yfr-oni' battery throughvthe-winding 'of relay* 1,25` l 531, inner-leftirontcontafct 'lot ,relay530 to"y groundat 'the outer right ./{ront contact ofrelay505,--B-elay531 `closes circuitsfroni Y Y i. vbitrrthronel@` the, meses#,520 .Whichcnf trols theoperation of switch 550, Aouter right -rontcontact of relay 531, right `tront `contact o1 relay 530, yback cont-actof .magnet 5211, outer lright front contact oit relay y'505' to ground.It'also opens the energizing cir- Y cuit of relay 530. Switch 550 isthen Vrotated under the control of magnet 520 until. it engages an idlesender which is characterized by battery through a resistance onconductor 601. llhen an yidle sender Ais reached a circuit is closed:troni battery, inner back contact of relay 701, resistance 700,conductor 601, iterminal served bybrush '522, corresponding to the idlesender, inner right contact of relay 505, yboth windings of vrelay 533,winding of relay 534, outer right contact of relay 505 to ground. Re-

lay 533 operates and short circuits its high resistance windingApermitting marginal relay 534 :to operate. The operation of relay 534closes a circuit from battery through stop imagnet521, contact of `relay534, outer vright'contact of relay 505 to ground.

Magnet `52 11operates and opens theloclr- Iing circuit of `relay 530 andthe energizing circuit l"for magnet 520. Relay 530 and :inagnet 520release. Relay 530 on releasing closes a holding circuit Vfor -maget 521over the inner left front contact of vrelay 531, lright back contact or'relay 530, outer right Contact ofrelay 505 to ground. 'The-release of'relay 530 also connects 'ground 'from the outer right contact of relay505, inner "lett back contact of relay 530, middle left front `Contactof relay 531, inner right front con- I' Atact of relay 505 Jto conductor601 in yshunt .of the windings of lrelays '533 and "534 so a circuitAfrom 'ground through resistance 536,*brush 523 and its correspondingcontact, conductor 602, left winding yof relay '603, outer left backcontact of relay 701,'w`inding of relay 702 to battery. Relay 702operates, but relay 603 vbeing marginal does not. vRelay 702 locks toits energizing circuit inde- ,pendent of the contact oztrelay 701.

1t also closes an obvious energizing circuit forrelay 701 which `inoperating, removes battery from conductor 601to mark the sender busy tovother link circuits. VThe Voperation of relay 535 also closes a circuitlfrom battery, through the winding of relay 205, lower contacts of cam214, conductor 529,

'brush 514 and the terminal served thereby,

left winding ofrelay 519, inneile'ft Contact pulses.

of relay "535, brush 524 a-nd its corresponding contact, right `windingof relay 603, left back contact `of ielay604,iiglit back contact ofrelay 703, outer left front contact of relay 702 to ground. Relays 5.19and 603 being-differential the completion of this circuit does not causelthe operation of either relay. Relay 205 operates and connects-the.trunk conductorsV 249 and 250 through to the pulsing Arelays of thesender, disconnecting it from the windings of relay 201. This relayreleases andireleases relay 207.

lRelay 702 in operating, also closes a circuit .from battery, throughthe win-ding ot relay 605, No. 1 terminal and brush 614 oft,Y

timing switch 600, left back Contact of relay 606, conductor v607,flower right contact ot cani 1000, lower left contact of cam 1001,conductor '1002, outer right contact of relay 702 to ground. Relay 605operates and :locks to its energizing circuit independent of 'the timingswitch. The operation of relay 605 initiates a timing operation whichwill 4be more completely described later.

Registration of @all by relay @all indica-tor pulses.

A pulsing circuitiextends from sender 104 Ethrough the ldistrict andoiiice selectors, conductor 249, left contacts of cam 203, outer left'front contact or" relay 205, lower right contact of cam 212, upperright contact of cam-221, lconductor '538, brush 516, middle rightcontact of relay 535,'brush 526, conductor '61.9, inner 'left'backcontact of relay 703, right :back contact ot relay 704, `wind- -ing ofmarginal relay 705, windingof negatively polarized relay 7 06, windingofpositively Vpolarized :relay 707 inner left back contact-of relay 704,left contacts of cam i900, conductor 618, brush 525, inner right contactof relay "535, brush 515, conductor v537, upper contacts of cam 220,youter right :front contact of relay 205, left contacts of cam 204,conductor 250 and thence Vthrough :the oi'lice and district .selectorsto the sender 'The completion of this circuit, due to the operation ofrelay 205, initiates certain operations Vat the sender v104 which resultin 4the transmission of Vcode impulses `to correspond to the number vofthe wanted line. For a description of these operations, refer- Ience maybe made to the above Vmentioned Patent No. 1,464,084 t@ A. E. Landen etai., issued August 7, 1923.

As previously indicated and relay 707 responds only to positive Assumethat the number of the wanted subscriber is CHElsea 5678. The code'impulses which Will'be transmitted to relay 705 'being finarginalresponds only to heavy impulses, .ielay 706 responds only to negativeYpulses lays 705an'd 706. .The operation of relay Vcurrent through theright Winding of yrelay .70.9v iS not sufficient to cause that Vrelay toop- Correspond to this designation are asv/fol,- lows: Y' e y I "IhearVr negatiy'e C l2) l lightiiegative light negative -r A,

H (4) l llight positive v `f "light negative Y j k L lightpositiver. Y`(8M heavynegative y A light negatiye'y j f f fr 51{ light negative jheavy `negative y f light'positive light negative o' j j heavy negativef '7 heavy negative lieJYy negative a A j '.l'glll'rpostive f 8.heavy"negativeV heavyfnegative The rst impulse overthe abovetraoedypulsingY -eireuit causes,thegoperationv ofV re- 706 closes aoircuitfrom loatteryv through the left windingl of relay Y709, Winding of relay1708, -lei't haelt Contact orV .relay 709,. Contact ofrrelay 706,conductor 7 30,V lower left oony tact of oainl003, lConductor 888, .toground. at the outer'left' front Contact ofy relay 702.v Relay 708operates in this'oireuit, lout the l crate `--The operation of relay 708closes a 'battervy, through the vleft Windingo'flrelay V709, Winding ofrelay.708,.right-.Windingof locking circuit for thatrelayextending fromrelayr709, inner left frontoontact ofv relay vk7 08 t0 groundedconductor y780.V Relay 709 does notoperatein this loeking'oireuit sinceitsjright energizing Windingqis shunted loyk `the energizing circuit ofrelay 708."

`Relay 7 08-in operating also eloses acircuit Afrom battery throughA the.Winding of relay A7 10,rleit hack eontaet'of relay 71'1, outer leftrentar-,t of vrelay 708, -to ground on Conductor v730. Relay 710operates and closesv a locking circuit 'forv itself through theWind-ingof relay 71.1, inner right front Yoontactjof relay 710 togrounded conductor 730. Relay 711A does not operate in `thisloolingeirouit, being shuntedby the energizing-oircuit of relay 710. Theoperation .of'relay 705-feloses a circuitk troni battery, through theni'inding oi' relay 802, Conductor 805, inner right back Contact ofrelay 711, ConductorV 731 right haek'contaot joi'relay709,`front1contaet of relay 70510.` ground. lRelay-802 operates "andlocks over its right Contact, Conductor 888, outer leftQfront Contact otrelay 702 to ground.V When this impulse oeases, the oir-v Cuit ofrelaysV 706 and 705 is opened and re-v lay 706 opens at its' eontaet'theenergizing circuit of 7 08, permitting relay` 709 to 'operate in thevloekingeircuit of relay 708;A

- lhenQthe next i-inpulseis received, only shunt of the Winding of relay:708 .Qand'fijeleasesthat relay. ith relayr1708wreleased the originalenergizing orouit "or`relayf71'0 `is opened,zbut a substituteapeirouitis already inner right oontaothof, relayV closed at the 709-" '1. iy i iSince relay1705 is fnot operated,y noneof the relayso'lthe register 800isjoperated in Y response to this, impulse. VAtftheend,of the impulselrelay 706: releases, releasingrelay 709 `which in turnopenstheenergizing eir- Q-:uit of relayy 7andpperinits relay '711 to operate inthe-'locking oireuit of relayl710. This oonipletesthe reception ofthetandem V.relay 706 Vis operated.[Relayf706 elo'ses atv itsi'rontroontaeta circuitthrough theleft holding `Winding Vand .left` front oontaotofrelay 709, front Voon'tamt'ofurelay 706,*toy grounded conductor` 7 80,V.Thlisgeirouit is` in hundreds digit. resulting, inthe operation of lrelay 802. 1f;

tion and locking offrelayl. 708'in the manner previouslydeserihed.vRelay. 7 08vin'f operatiing ,closes a circuiti'roin loattery` through'the 1Winding of` relay-712, left back contact.of

relayY 7118, inner left/front contaelfoi'v relay 1711, outer left frontContact of relay 708 to grounded oonduetor730. Relay 7.12'oper- `atesand looks through the-Winding of' relay 713 to grounded conduetor730.#`Atthe end l of' the first pulse, relay/.70.6releases and relay '709,operates in the ulocking-eireuit lof l.relay 708., The next pulsebeingalight positiye pulse'oauses; the operationof l,relay -707 which inturn'elosesa circuit from: battery through the Windin'gofrelay818,'oonductor 815, right haelroontaet of relay ,714, outer right frontContact of relay-712,@eonduotor V783, right front contaetofrelayi`708,conta`ot of relay 707 2te-grounded ,conductor 730.

Relay 813operatesand loels overitsrin'lit" `liront Contact to groundedConductor 888.gif

In respOnSfto the next impulse relay706 alone is operated,:eausingiby,itsroperation Y' I the release oirelay708, .and atitsirfelease, the release of relay .7 09 and VYtheoperation offre-,y

lay ,713. in.` theI locking QoiroutofV relay 71,2.

In response to thefirstZ 'inpu and710, conductor 732, rightjbaokoontaetof relay. "708,A lfront oontaotlof'p. relay 707,140 fgroundedoondctorj 'Relaly821'Qperates and looks to. grounded 'conductor888i ni response tu the-second' baptis, yrelays liao moana #zot/.areoperated, re aytoe Causing

